Brake



lli: 74

INVENTOR.

A TTORNEY July 20, 1937.

A. c. CHAMBERS BRAKE Filed Oct. 18, 1955 &

Patented ,italy 26)?, HQE? A essere aosasri l,

anche Allen C. Chambers, Detroit, Mich.,

assigner to Bendix Products Corporation, South Bend, Ind.,

a corporation of l Application october 1s. i935, serial No. 45,571 z claims. (c1. lss-152) This invention relates to brakes, and is illustrated as embodied in an internal expanding brake for an automobile. An object of the-invention is to provide a simple and powerful brake l10 from each other, so vthat they are individually shiftable' to anchor at either end according -to the direction of drum rotation, and are actuated by floating wedges carried by a pair of levers spread apart by pressure-balancing means,' 15 preferably a cylinder containing I a pair of pistons connected respectively to the levers.

The above and other objects and features of the invention, including various novel combinations of parts and desirable particular constructions, will be apparent from the following description of the illustrative embodimentfshown .in the accompanying drawing, in which:

Figure 1 is a vertical section through the brake, just inside the head ofthe brake drum, showing the 'brake shoes in side elevation; d

Figure 2 isaI partial section through the brake, on the line 2-2 of Figure 1; and

Figure 3 isa partial section on the line 3-3 of Figure 1. v)

Theillustrated brake includes a'rotatable drum I0, at the open sideUof which is arranged a support `such as a backing plate i2, shown as having spot-weldedl or otherwise cured thereto,

'section shoes across the drum from each other, a pair of angle-shaped steel stampings il and i6. which project into the drum immediately inside the A thereof :to form anchors taking the braking torque.

Between these anchors are arranged two T- i8 and 20, the webs of which are engageabie with the anchors at their opposite ends, and whichwebs project past said anchors and radially inside thereof as thrust portions carrying spindles 22 on which pairs of thrust rollers 2 4 are mounted on opposite sides of the webs.' The shoes are normally heldin retracted position, against -the anchors, bymeans such as.

return springs 26 tensioned between the shoes. The brake is applied by novel means shownas including two levers 28 and 2l. pivoted on the ShOeS,

'substantially equal force lsaid plate adjacent the backing -plateinside the drlmi and movable in a plane beside and paralleling the backing plate.

These levers have oatingly connected thereto,

for example by links 32, wedges 34 acting on the rollers 24. As shown in Figure 2. the wedges.

may have positioning ribs 3B projecting between the rollers 24.

The levers 28 and '30 are applied by pressurebalancing means, preferably of the hydraulic type. I prefer to utilize a double-ended hydraulic cylinder 38 mounted on the backing plate inside the drum approximately opposite the center of the `shoe I8, and containing two-pistons 40 and 42 connected. by means such as piston rods or links AM respectively and 30. l

While one illustrative embodiment hasr been described in detail. it is not my intention to limit the scope of myiinvention to that particular embodiment, or otherwise than by the terms of the appended claims.

I claim: I f

1. A brake comprising a drum having a backing plate at its open side, anchors projecting 'from said plate adjacent the braking surface of the drum and arranged v'across the drum from each other, shoes arranged within the drum and each engageable with said anchors at `its opposite ends, a pair backing plate across the drum from each other and each carrying an outwardly movable floating wedge engageable with the ends of both shoes, ard pressure-balancing means acting with on said levers.

2. A brake comprising a drum having a backing plate at its open side,

brakingv surface of the drum and arranged across the drum from each other, shoes arranged within the drinn and each engageable with said anchors at its opposite ends, a pair of levers fulcrumed on the backing plate across the drum from each other inside of `the drum and each carrying an outwardly movable floating wedge engageable with the ends of both a double-ended cylinder mounted inside the drum on said backing plate adjacent the central portion of one shoe, and pistons in said cylto the levers 28 of levers fulcrumed'on the v35 anchors projecting from' 

